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<a name="AUTOMATIC-and-STATIC-attributes"></a>
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Next: <a href="Extended-math-intrinsics.html#Extended-math-intrinsics" accesskey="n" rel="next">Extended math intrinsics</a>, Previous: <a href="Type-variants-for-integer-intrinsics.html#Type-variants-for-integer-intrinsics" accesskey="p" rel="prev">Type variants for integer intrinsics</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="AUTOMATIC-and-STATIC-attributes-1"></a>
<h4 class="subsection">5.1.25 <code>AUTOMATIC</code> and <code>STATIC</code> attributes</h4>
<a name="index-variable-attributes"></a>
<a name="index-AUTOMATIC"></a>
<a name="index-STATIC"></a>

<p>With <samp>-fdec-static</samp> GNU Fortran supports the DEC extended attributes
<code>STATIC</code> and <code>AUTOMATIC</code> to provide explicit specification of entity
storage.  These follow the syntax of the Fortran standard <code>SAVE</code> attribute.
</p>
<p><code>STATIC</code> is exactly equivalent to <code>SAVE</code>, and specifies that
an entity should be allocated in static memory.  As an example, <code>STATIC</code>
local variables will retain their values across multiple calls to a function.
</p>
<p>Entities marked <code>AUTOMATIC</code> will be stack automatic whenever possible.
<code>AUTOMATIC</code> is the default for local variables smaller than
<samp>-fmax-stack-var-size</samp>, unless <samp>-fno-automatic</samp> is given.  This
attribute overrides <samp>-fno-automatic</samp>, <samp>-fmax-stack-var-size</samp>, and
blanket <code>SAVE</code> statements.
</p>

<p>Examples:
</p>
<div class="example">
<pre class="example">subroutine f
  integer, automatic :: i  ! automatic variable
  integer x, y             ! static variables
  save
  ...
endsubroutine
</pre></div>
<div class="example">
<pre class="example">subroutine f
  integer a, b, c, x, y, z
  static :: x
  save y
  automatic z, c
  ! a, b, c, and z are automatic
  ! x and y are static
endsubroutine
</pre></div>
<div class="example">
<pre class="example">! Compiled with -fno-automatic
subroutine f
  integer a, b, c, d
  automatic :: a
  ! a is automatic; b, c, and d are static
endsubroutine
</pre></div>




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